Even a relatively small regional nuclear war could trigger global cooling, damage the ozone layer and cause droughts for more than a decade, researchers say.

These findings should further spur the elimination of the more than 17,000 nuclear weapons that exist today, scientists added.

During the Cold War, a nuclear exchange between superpowers was feared for years. One potential consequence of such a global nuclear war was “nuclear winter,” wherein nuclear explosions sparked huge fires whose smoke, dust and ash blotted out the sun, resulting in a “twilight at noon” for weeks. Much of humanity might eventually die from the resulting crop failures and starvation. [Doomsday: 9 Real Ways the Earth Could End]

Today, with the United States the only standing superpower, nuclear winter might seem a distant threat. Still, nuclear war remains a very real threat; for instance, between developing-world nuclear powers such as India and Pakistan.

To see what effects such a regional nuclear conflict might have on climate, scientists modeled a war between India and Pakistan involving 100 Hiroshima-level bombs, each packing the equivalent of 15,000 tons of TNT — just a small fraction of the world’s current nuclear arsenal. They simulated interactions within and between the atmosphere, ocean, land and sea ice components of the Earth’s climate system.